The invention relates to housings or cabinets for loudspeakers, and to a method of making loudspeaker housings. More particularly, the invention relates to a method of making a loudspeaker housing and to a loudspeaker housing which is a one-piece or composite casting.
At the present time, housings for electroacoustic transducers (hereinafter called loudspeakers) are made of wood, a plastic material or a ceramic material. The nonlinear distortion factor (also known as relative harmonic content, k-factor or klirrfactor) of wood and plastic material is relatively low, and the damping characteristics of these materials are rather satisfactory when the demands upon the quality of amplified sound are not very high. If the loudspeaker housing is to be used as part of a high-quality sound generating and amplifying equipment, especially as concerns its internal damping characteristics, wood and/or a plastic material cannot meet the requirements and, therefore, the housings of loudspeakers forming part of a high-quality sound generating and amplifying system are often made from a ceramic material. However, it has been found that loudspeakers having housings made of a ceramic material also fail to meet the requirements which are imposed upon high-quality sound generating and amplifying equipment.
In summation, heretofore used materials for the making of loudspeaker housings or cabinets exhibit unsatisfactory damping characteristics (such characteristics are typical of loudspeaker housings which are made of particle board), or the materials are satisfactory acoustic conductors but exhibit a selective sound transmissivity (examples of materials for such loudspeaker housings are concrete, marble and natural stone). In addition, all of the presently utilized materials for the making of loudspeaker housings exhibit the drawback that they "live their own musical life" which is evidently undesirable for a number of reasons.